The present invention generally relates to machine gun apparatus and, in a representatively illustrated embodiment thereof, more particularly relates to a specially designed machine gun bolt pin locking apparatus.
In a conventional machine gun such as, for example, a .50 caliber machine gun, the body or receiver portion of the gun has disposed therein a bolt assembly which reciprocates forwardly and rearwardly as the gun is fired. The bolt assembly is strongly spring-biased in a forward direction, and carries a bolt pin member which projects outwardly through a horizontally elongated slot on a vertical side wall of the receiver for reciprocation with the bolt assembly. To enable the manual rearward movement of the bolt assembly, an external charging handle is typically secured to the outwardly projecting bolt pin.
Access to the interior of the receiver, and the bolt assembly therein, is provided by means of an access door carried by the receiver. The interior of the receiver is typically accessed through this door to clear ammunition jams, and, during an idle period of the gun after a firing sequence, to hold the bolt assembly (and the next-to-be fired round which it caries) rearwardly away from the still-hot barrel to prevent an undesirable “cook-off” firing of the next round by the heat of the barrel.
As is conventionally practiced, this holding of the bolt assembly in such rearward orientation away from the barrel, is accomplished by opening the receiver access door, pulling the bolt assembly rearwardly using the exterior charging handle secured thereto, and then pivotally moving a round extractor structure within the interior of the receiver until the round extractor is braced against the receiver interior in a manner preventing the spring-biased bolt assembly from snapping back to its original forwardly disposed position within the receiver.
Unfortunately, injury to operators' hands and fingers within the receiver interior is not an uncommon occurrence due to slippage of the repositioned round extractor structure which permits he rearwardly held bolt assembly to rapidly and very strongly snap back to its forwardly disposed position within the interior of the receiver. For this reason it can readily be seen that a need exists for a safer and more reliable technique for holding the spring-loaded bolt assembly in a rearwardly disposed orientation within the interior of the receiver. It is to this need that the present invention is directed.